IPA: /səˈspɪʃəsli/
KK: /səˈspɪʃəsli/
In a manner that makes someone feel doubt or distrust about something or someone.
She looked at him suspiciously when he arrived late without explanation.
Suspiciously → It is formed from "suspicion" (from Latin "suspicio", meaning a looking up or a doubt) and the suffix "-ly" (meaning in a manner of). The word "suspiciously" means in a manner that expresses doubt or distrust.
Think of 'suspicion' as a feeling of doubt, and remember that 'suspiciously' describes acting in a way that shows that doubt.